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    Dog Traits Are Determined By Genetics

    The waiting room at a vet’s office is like a smorgasbord of different types of dogs. Some are small with black curly fur; others may be big, white, and fluffy.

    There’s a wide variety of dog personalities and physical traits. However, this degree of variation all stems from one singular place: DNA. 

    Through the study of DNA, we can learn more about how genetics plays a role in defining canine characteristics.

    Keep reading to learn more about how DNA is inherited in dogs, and how genes determine everything from floppy ears to coat color. 

    Inheriting Traits

    Just like in humans, a dog’s DNA contains important genetic information that will guide the dog’s cell functions. DNA is like a treasure chest that holds all the important information the body needs. It’s the molecule that contains the genetic code of any living organism like people, animals, plants, and even bacteria.

    Your dog received two copies of DNA, one of which came from each parent. The distribution of DNA your dog inherits is a random process. If you’ve ever seen a litter of puppies that looks surprisingly and remarkably different, this is because the specific DNA makeup of each puppy was inherited randomly, and therefore two siblings can look very different from one another. 

    Within DNA are genes. These genes are responsible for determining specific traits about your dog. These traits include coat color, eye color, type of ears, and even important health information like susceptibility to certain diseases and physical problems. 

    Recessive And Dominant Traits In Dogs

    Similar to humans, some traits that your dog inherits are recessive and some are dominant. To put it simply, a dominant gene is a term to refer to the relationship between two versions of the same gene. Everyone receives a version of a gene from each parent, and these are known as alleles. If the two alleles of a gene are different, then only one allele will be expressed, making that one the dominant gene. The other allele is then masked and is known as the recessive gene.

    Dominant traits are passed on to a dog from either its mother or father. A dominant trait only needs one copy of a certain gene to be passed on to the puppy in order for the dog to express that trait. Examples of dominant genes in your dog would include coat color and whether that right ear flops down or not. 

    A recessive trait functions differently than a dominant trait. While a dominant trait only needs one gene to pass on to the dog, recessive traits require two copies, one copy of which comes from each parent. It’s possible that your dog’s ancestry had a hidden recessive trait for many generations. Only when a puppy receives two recessive traits, one from each parent, does the trait become expressed in the dog.

    How Genes Play A Role In Dog Breeds

    Dog breeds, like certain human populations, will share similar genetic information. This is why, for example, you might get a certain population with a predisposition to certain diseases. Dogs are no different. It’s why black labradors have similar coats, nose, face structure, bodies, ears, and fur. 

    There are a few identified genes that contribute to your puppy's coat color. Some genes produce black pigment, while others give the foundation for brown or yellow coats.

    From there, dominant and recessive genes come into play and are combined with other genetic markers that will determine the strength of pigmentation, patterns, and more. So, if your dog is purebred, it likely shares much of the genetic information with its specific breed and therefore exhibits similar traits and characteristics. 

    Coat color isn’t the only factor at play. Genes also determine the texture of your dog’s fur, its length, and whether it's straight or curly. Other factors can include ears, colors of paws and nose, and so much more. 


    Many of us wish our dogs could speak to us and tell us about their parents, ancestry, and heritage. The next best thing we have is to study the DNA of dogs to understand how and why our beloved pets look and behave as they do. Accordingly, more owners are turning to pet DNA kits to learn about their dog’s breed to make more proactive health decisions and get to know them on a deeper level.